It is well known in the art to control the displacement of both a variable displacement pump and a variable displacement motor by controlling a source of pressurized fluid being directed to the respective displacement controllers. In these known systems, the displacement controllers are controlled strictly by the pressure being directed thereto in response to operator movement of an input lever. When controlling the displacement controllers responsive to a pressure input only, some type of feedback apparatus is necessary to insure that the controller has moved to the desired displacement position as directed by the input signal. The addition of the needed feedback apparatus adds complications and cost to the system.
The present invention is directed to overcoming one or more of the problems as set forth above.